The use of fuel cell power plants to provide electric power to electric vehicles is being proposed by many sources. In many parts of the world, the fuel cell power plant must be able to withstand freezing temperatures. One approach is for such fuel cells to utilize a freeze-proof coolant solution, such as the common ethylene glycol antifreeze solution in water. However, ethylene glycol has a very high tendency toward poisoning the membrane of a PEM fuel cell as well as the catalyst, and must therefore be completely isolated from the fuel cells.
Cooler plates are easily provided which will totally contain the coolant within them, thereby posing no threat to the fuel cells from the coolant solution. However, a problem heretofore has been that getting the coolant into the cooler plates has required that there be a manifold which in turn may subject the joints between adjacent fuel cells, as well as the joints between cooler plates and fuel cells, to leakage of the coolant, which thereby can enter and poison the fuel cells themselves.